HECnet is a DECnet that connects different people who play around with
different DEC machines. The network should not be regarded as a serious
networking setup, nor should it be expected to work 24/7. It's a hobby
project between people who think it's fun to create a DECnet network.
HECnet is basically a DECnet phase IV network. Currently, the main
router is a PDP-11 running RSX-11M-PLUS. The machine is located in Uppsala,
Sweden.
The connectivity between nodes can be anything that works. The current
connectivity is with an ethernet bridge between sites, DECnet over IP using
Multinet on VMS, and DECnet over IP on Cisco. Other solutions that
have been used are a virtual serial async. connection talking DDCMP. Other possibilities
are GRE and DECnet over IP.

How do I get connected?

In order to connect to HECnet, you need to talk with the resposible
person (currently that is Johnny
Billquist <bqt@update.uu.se>)
about allocating a node name and number. The node names in DECnet phase
IV must be unique within the whole network, so this have to be coordinated.
(Well, technically, you can have local node names defined for machines
at every node in DECnet, but that isn't much fun, is it?)
Secondly, you need a node number. What number depends on where you get
connected.
After that, you need to set up a connection to whatever DECnet router
you should be connected to. How this is done depends on what kind of connection
you will have.
An ethernet bridge will require a separate Unix machine on the same
ethernet segment as your DECnet machines, which then bridges your
ethernet with the rest of HECnet. This is not a full bridge, but only
one that transmits packets for DECnet, so the rest of the network is not
compromised.
On this Unix computer, you need to compile, configure and run the ethernet
bridge program, which can be found >>here<<.
The configuration requires that you talk with someone else running
the bridge, and agreeing on some parameters for the bridge. You should
probably join the HECnet mailing list at this stage before expecting
things to start working.